AFRICAN WALNUT SEED OIL ENRICHED DIET REDUCES PROSTATE CANCER INCIDENCE IN WISTAR RATS

*Esosa Samuel Uhunmwangho, Onoriode Oyiborhoro and Osungbemiro Bamikole Walter

ABSTRACT

African Walnut (Tetracarpidium conophorum- Mull. Arg) is a perennial climbing shrub which grows mainly in West Africa, especially in Nigeria. The seeds are commonly processed by boiling and consumed as a snack. This study investigated the possible inhibition of 3-methylcholanthrene (MC) induced prostatic carcinogenesis and expression level of ethoxyresorufin-O-de-ethylase (CYP1A1), benzoxyresorufin-O-dealkylase (CYP1B1) and pentoxyresorufin-O-dealkylase (CYP2B1) activities by African walnut seed oil extract in male Wistar rats. The seed oil was extracted with n-hexane using Soxhlet apparatus. 60 Wistar rats of an average weight of 40-45g were randomly divided into four major groups of 15 rats each. Group A and B animals were fed for 12weeks with diet containing 10% of African walnut seed oil. Group C and D were fed for 12weeks with diet containing no African walnut seed oil. Group B and C animals were administered with 3-methylcholanthrene (200mg/kg) intraperitoneally after 4weeks of feeding. Results showed that group B had a significant decrease in the expression of CYP1A1, CYP1B1 and CYP2B1 enzymes (p<0.05) compared to group C. Prolonged latency period, reduce tumor weight and size characterized animals in group B. Histological analysis of the liver revealed that the progression of carcinogenesis was more rapid in animals that were not pretreated with African walnut seed oil, which is indicative that African walnut seed oil enriched diet oppose prostate carcinogenesis induced by MC.

Keywords: 3-methylcholanthrene, African walnut, Prostate gland, Cytochrome-P450.